I've got a batch of cider in a vat. It's my first one. It's made from pasteurized apple juice, no additives. I gave it some sugar to get the OG up to my desired value, and think I gave it too much. As the rocket scientist said to the fire department: "My calculations were off." (I've been brewing beer from home-brew kits for some time, and have made notes of the fermenting range of Cooper's beer yeast in wort. Since that's the yeast I'd decided on, I aimed for an OG that would get the finished cider to a density slightly lower than that of a commercial brand which I tested and enjoyed.) (The yeast actually behaved as predicted, it was human error that made the initial sugar concentration too high.) (Could I get another set of parentheses here?) (I certainly could.)

I pitched the yeast even though I'd measured the OG to be higher than desired, and the fermentation went well for about a week. Then, nothing. I tasted it, and found it cloyingly sweet, although promising. "So", thinks I, "the beer yeast has reached its alcohol tolerance and has left too much sugar in my must, because I've been an idiot and given it too much starting sugar! What to do? Aha! I shall add some wine yeast. That's got a higher tolerance, and so should be able to ferment away most of the residual sugar!"

It was no sooner thought than done. But the blasted thing is still just sitting there. It's been a couple of days now. No activity in the lock, no change in specific gravity, nothing. I'm thinking about just bottling it to see how it turns out (I've got aunts who will drink cheap dessert wine without blinking), but I'm afraid that the fermentation might start in the bottles, thus effectively making me a manufacturer of bombs. I don't want to do that, because I think maybe bomb making is heavily taxed. (Hmm. Would yeast bombs count as biological weaponry, I wonder?) I'm not into killing off the yeast artificially, so the "cider" either goes into bottles or down the drain.

So, finally, my question is: Why won't the wine yeast start fermenting? Is it because the beer yeast has made "home turf" of the must? Is it just being bloody-minded? Or is the sugar concentration actually too low for the wine yeast to get to work? (This begs the question "Well, what is the gravity now, Dumbo?", and as I said, I can't remember at the moment. But I'll get it on the board as soon as I get my notebook. In the mean time, such answers as "Usually, wine yeast requires a gravity of _____ to start fermentation. That might be your problem right there." will be appreciated.)

You know, it wasn't until recent history that sweet wines were so frowned upon... until what... the 50s I seem to remember, sweet wines were in vogue. You could start a comeback... or just ship it to me. <smiles>

Ah. I wasn't intentionally badmouthing sweet wines. I like a good glass of port or madeira as much as the next man. (Or maybe more.) Still, I balk at comparing what's (still not) fermenting at home with such delicacies... :-)

ScottT, if by proofing the yeast you mean hydrating and nourishing it in a separate container before pitching, I did. It showed every conceivable sign of life before I added it to the must. Imagine, if it hadn't stopped fermenting, it might have been ready for school by now!

Since the beer yeast used up all of the O2, the wine yeast has to go straight into alcohol production without a growth phase. This means there aren't many of them and the fermentation will be slow. I would suggest you get some more wine yeast and make a starter. Re-hydrate the yeast in about a cup of water, add a cup of your cider and shake it well to aerate. Give it a couple days to grow. Add it to the pail.

Do not aerate your cider directly to try and get the yeast going. Too much chance of oxidation.

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